Digital signature vs electronic signature

One is a category, the other is a technology

An electronic signature is any electronic mark made with the intent to sign. A drawn squiggle on a touchscreen, a typed name in a signature box, a checkbox saying you agree, a reply saying "I approve" — all of them are electronic signatures. The category is defined by intent, not by mechanism.

A digital signature is one specific technology: a cryptographic operation using a private key that binds the signature to the document's exact contents and to a verified identity. Change one byte of the file afterwards and the signature stops validating.

So every digital signature is an electronic signature, and the overwhelming majority of electronic signatures are not digital signatures. That is the whole distinction, and it explains why the two words are not interchangeable even though almost everyone treats them as if they were.

What a digital signature actually proves

The cryptography delivers three specific guarantees that an image of a signature cannot.

• Integrity. The signature is computed over the document's contents, so any later modification invalidates it. A reader will say so.
• Authenticity. The signing key is tied to a certificate issued by a certificate authority that verified who the holder is, so the signature identifies a person rather than asserting a name.
• Non-repudiation. Because only the private key holder could have produced it, the signer cannot credibly deny having signed — which is precisely the property a drawn squiggle lacks.

Are electronic signatures legally binding?

In most of the world, yes — for most documents. In the United States the ESIGN Act of 2000 and the state-level UETA give electronic signatures the same legal effect as handwritten ones, provided the parties intended to sign and consented to do business electronically. The European Union's eIDAS regulation does the same across member states.

eIDAS is worth knowing about because it names three tiers rather than one. A simple electronic signature is the broad category. An advanced electronic signature must be uniquely linked to the signer and detect subsequent changes — in practice, a digital signature. A qualified electronic signature adds a certificate from a government-accredited provider, and is the only tier that automatically carries the same legal weight as a handwritten signature across the EU without further argument.

The exceptions are narrow but real. Wills, some family law documents, certain property transfers and some court filings still require wet ink or notarisation in many jurisdictions, and the specifics vary by country and by state. This is general information rather than legal advice — for anything consequential, check the requirement for your jurisdiction and document type.

Which one you need

For the ordinary run of things — an NDA, a lease, a vendor agreement, a consent form — a plain electronic signature is legally sufficient and is what almost everyone uses. The practical evidence that matters in a dispute is usually the surrounding audit trail rather than the mark itself: who signed, from what address, when, and what they were shown.

You want a genuine digital signature when tamper-evidence is the point. Documents that will be filed with a regulator, records that must demonstrably not have changed since signing, anything where the counterparty may later dispute the contents rather than the intent. Also anywhere a jurisdiction specifically requires an advanced or qualified signature.

The honest summary: most of the time an image of your signature placed on a page is both adequate and normal. Occasionally it is not remotely enough, and knowing which situation you are in is the entire value of the distinction.

What placing a signature on a PDF really does

Worth being clear about the mechanics, because the interface hides them. When you draw or type a signature and drop it onto a page, you are embedding a small image at a chosen position. The page's real text and vector content is untouched; only the signature itself is a picture.

That is an electronic signature. It carries no cryptographic binding to the document, and nothing stops someone extracting the image or placing it on a different page — which is exactly why the audit trail around it does the evidential work.

One practical step improves it: flatten the document afterwards. An unflattened signature sitting as an annotation can be moved or deleted by anyone with an editor. Flattened, it becomes part of the page.

Frequently asked questions